Understanding what happened to Rescue 116

The aim of the Air Accident Investigation Unit report is not to apportion blame

Searching for the  missing crew members of Rescue 116. Photograph: Colin Keegan

Searching for the missing crew members of Rescue 116. Photograph: Colin Keegan

 

There are many links in an accident chain. The preliminary Air Accident Investigation Unit report on Rescue 116 follows a prescribed formula, setting out the data that exists at this point in time.

Its task is to be scientific and unemotional. We should respect that process. It is a difficult one, one designed to gather as much data as possible so that this chain, and all its links, can be analysed forensically.

It is repeatedly stated that the aim of this report, or indeed any report coming from this agency, is not to apportion blame. We should keep that in mind at all times when digesting its contents.

The mission of Sikorsky S92, a state-of-the-art machine, is described in some detail and outlines how the medical evacuation (medevac) was requested by a fishing vessel (FV), and how the Irish Coast Guard responded.

For more than 25 years helicopter SAR missions have been undertaken by the Air Corps or by the Coast Guard. Up to nearly its tragic end, it followed the same steps as hundreds of previous missions.

Available data

The report outlines the initial available data facing R116, flown by an experienced crew, in a familiar environment, in weather that would be considered poor weather, but manageably so by Irish SAR crews.

The report says the Enhanced Ground Proximity Warning System (EGPWS) does not include the 281-foot-high Black Rock, adding that it is continuing to discuss this omission with the manufacturer.

However, it also states that EGPWS is not a primary navigation system. Rather, it “is a system designed to alert pilots if their aircraft is in immediate danger of flying into the ground or an obstacle”.

Primary navigation establishes an aircraft’s position. Sometimes, it can be done looking out from cockpit windows by day and in clear weather. The challenge in night rescue and navigation is that this may not be possible.

In the weather conditions of that night – mist and low cloud – establishing spatial awareness and navigating accurately would have been supported by layers of conventional navigation: admiralty charts and coastal maps, together with GPS, etc.

In days gone by this would have included identifying lighthouses by their unique beacon flashes. The report states that the crew were following their navigation route, one that would have included the identification of Black Rock’s height above sea level.

Weather radar

The weather radar on the Sikorsky S92 helicopter is standard issue and would be used to avoid bad weather by tilting its beam upwards to identify cumulonimbus, or thunderstorm cells.

In “mapping” mode, it is used to look ahead and, with a downward tilt, to see coastal outlines and shapes and islands such as Black Rock. The investigation analysis to come will examine how radar is used by Sar crews, particularly that night.

“Follow-nav” or “back-up navigation” includes all members of crew. This would involve the winching crew, in the helicopter cabin to the rear of the flight deck, tracking position and plotting on admiralty charts and looking ahead with the infra-red camera.

However, warm-sector misty weather conditions degrade infra-red camera performance and no doubt this will feature in further analysis of the accident data. Neither pilot had been to Blacksod in recent times, the report notes.

However, robust and time-proven Sar procedures are designed and have evolved for such scenarios. Helicopters from the UK and Ireland assist each other all the time, operating in each other’s at times unfamiliar operational areas.

Coast Guard units on land and sea, RNLI crews, Mountain Rescue, Civil Defence, Defence Forces and gardaí personnel frequently leave their familiar “patches” and assist other units in less familiar terrain.

Thank God for the rescuers in all agencies of our rescue network. Please God, le cuidiú Dé, let us find Paul Ormsby and Ciarán Smyth. Ar Dheis Dé go raibh a n’anamnacha dílse.

Formerly Irish Coast Guard’s Shannon-based chief pilot, David Courtney carried out over 300 emergency missions from 1988 to 2001 with both Air Corps and Irish Coast Guard. He is the author of Nine Lives (Mercier Press)